PO0700 trannie code won't go away

[filthyfingernails]

Well I'm hopefully down to the last code to be cleared on my kid's "free" Jeep .
Her recently acquired 2000 XJ Sport I6 4.0L automatic trans. 4wd looks like its never been maintained (chick car). It has 150k miles on it but beneath all the crud seems to be a great Jeep. With CA emissions I had to install all 4 O2 sensors. That cleared up all the codes that had stacked up over the years. But this 0700 code won't clear. The XJ runs fine, shifts smooth.
I've looked at other threads and forums and usually the 0700 code is not alone. Some other failure seems to go along like a solenoid or gear ratio failure. This is just the 0700 nothing else.

What gives? Anyone? Anyone?

edit: Had no backup lights. I removed and rebuilt the NSS. still no BU lights. Then discovered that fuse #10 on the junction block was missing. Not blown, not on the floor... just gone. Replaced the fuse, bingo! Got backup lights. Code 0700 still won't go away. Tried clearing it, disconnecting the batt. cables overnight... no dice.

 

[jbahr]

The PO700 has to be removed with a scanner. Even though the problems are fixed the code will still remain until you have it electronically removed. I had the same situation with my 98.

 

[Bryan C.]

Well I'm hopefully down to the last code to be cleared on my kid's "free" Jeep .
Her recently acquired 2000 XJ Sport I6 4.0L automatic trans. 4wd looks like its never been maintained (chick car). It has 150k miles on it but beneath all the crud seems to be a great Jeep. With CA emissions I had to install all 4 O2 sensors. That cleared up all the codes that had stacked up over the years. But this 0700 code won't clear. The XJ runs fine, shifts smooth.
I've looked at other threads and forums and usually the 0700 code is not alone. Some other failure seems to go along like a solenoid or gear ratio failure. This is just the 0700 nothing else.

What gives? Anyone? Anyone?

edit: Had no backup lights. I removed and rebuilt the NSS. still no BU lights. Then discovered that fuse #10 on the junction block was missing. Not blown, not on the floor... just gone. Replaced the fuse, bingo! Got backup lights. Code 0700 still won't go away. Tried clearing it, disconnecting the batt. cables overnight... no dice.

P0700 is a code that says there is a trans controller fault present. Time to get a scanner that will get into the trans controller and figure out what is going on with it.

 

[filthyfingernails]

Hmmmm, I guess my newly acquired UIFTECH U381 Memoscan is too wimpy to:

1. Clear the code even temporarily.
2. Diagnose with any detail.

Since a NY State inspection is now overdue, I guess its time to go to the dealer, and I hate that.

 

[aparke4]

i had a hypertech programmer and it caused this code to pop up even after setting it back to stock... it runs fine and the check engine light does not come on but when diagnosed a obd reader will pick up the code... i think the programmer did something to cause this... i might need to take it to a repair shop to clear this... i have already reset the computer to no avail...

 

[filthyfingernails]

So now my daughter visits looking for an update on her XJ. I tell her that all codes have been cleared except a single trannie code. And she says, "Oh, didn't I tell you? Sometimes it slips in first gear." :smoker:

 

[filthyfingernails]

Uh Oh. Brought the XJ to my friendly local mechanic. He cleared the code, I think. The CEL is now off. I got all excited, and asked wheres the inspection sticker? He said Forget it. The code is still in there. You need to go to the dealer.

He says he thinks I need a new TCM. He also said he only reads the PO0700 code and none other.

Anything else I can try besides cleaning contacts. I'll be doing that all day today.

 

[filthyfingernails]

Opened up all the connectors cleaned all the contacts. Lotsa crud on the connector blocks but the contacts looked clean. Still have that single PO700 code.

All I can think to do is replace the TCM and maybe the TPS???

Is this a blog?

 

[lawsoncl]

A Code 0700 all by itself can mean the TCU wasn't responding. If the TCU has no power, it will try to start in 4th gear with the shifter in (D). Maybe thats what the daughter meant by "slipping"? Maybe check the tranny fuse and the connector to the TCU?

 

[filthyfingernails]

Thanks! Good thought. Hope to do that tomorrow! Thanks again. TCU is the same as TCM right?

 

[lawsoncl]

Thanks! Good thought. Hope to do that tomorrow! Thanks again. TCU is the same as TCM right?

Yes.

 

[scoobyxj]

At this point I would take it to a dealer, or a shop that has a DBRIII scan tool. Your typical shade tree scanners will not go deep enough.

P0700

EATX Controller DTC Present


This SBEC III or JTEC DTC indicates that the EATX or
Aisin controller has an active fault and has illuminated the
MIL via a CCD (EATX) or SCI (Aisin) message. The
specific fault must be acquired from the EATX via CCD or
from the Aisin via ISO-9141

If you haven't already I would check the connectors on the TCM, and the grounds for it. Something you may have not of though of is to check the wiring where it passes though the fire wall. Also if you didn't see it there is a connector right behind the coil rail. I have had tranny codes come up after changing the plugs from disturbing that plug.

 

[scoobyxj]

At this point I would take it to a dealer, or a shop that has a DBRIII scan tool. Your typical shade tree scanners will not go deep enough.



If you haven't already I would check the connectors on the TCM, and the grounds for it. Something you may have not of though of is to check the wiring where it passes though the fire wall. Also if you didn't see it there is a connector right behind the coil rail. I have had tranny codes come up after changing the plugs from disturbing that plug.

After doing more reading on this I have come to understand that the Aisin controller is a generic Chrysler transmission controller, and not specific to the AW-4. The ISO-9141 is Chrysler specific software used to retrieve fault info from the controller.

 

[lawsoncl]

After doing more reading on this I have come to understand that the Aisin controller is a generic Chrysler transmission controller, and not specific to the AW-4. The ISO-9141 is Chrysler specific software used to retrieve fault info from the controller.

I'm not sure on newer than 1996, but the older TCUs are definitely marked Aisin-Warner and specific to the AW4 solenoid setup. ISO-9141 is an interface specification covering the hardware and signalling. The ECM and TCU share the ODB bus so they would have to use the same interface spec.

 

[filthyfingernails]

Since its been too cold here in UNY to do anything, I've been sketching the trannie circuits from the service manual... PCM --> TCM--> NSS--> listing fuses, connectors and splice locations.
I brought the XJ into the garage overnight. Might fireup the propane heater and work on it today...Yeah Right :shiver:

 

[Scrappy Doo]

I had a similar problem, and I removed all the wire covering unter the truck and found where the solenoid harness was rubbing against the transmission case. It had worn all the way through the wires, and gave the p0700 code. I replaced them, replaced all the spiral wrap and all is well, and has been for a few weeks now. Good Luck, don't forget to check the connector on the TCM.

 

[filthyfingernails]

YEEEHA! Thanks to all for the help. I've gone from clueless to codeless. Replaced 4 02 sensors, rebuilt the NSS, and finally replaced the TCM (ebay) and the last code went away. Now I need to put on about 200 code-free miles to qual for a NYS inspection sticker.

:smoker: